head to head
Neither is simply harder - they are hard in different places. Grand Theft Auto V demands more reads; Panzer Dragoon II Zwei demands more execution.

Execution · Practiced Mastery
Sandbox crime playground spanning shooting, driving, and a persistent online economy.

Execution · Practiced Mastery
A Saturn rail shooter where memorizing choreographed waves and routes evolves your dragon.
Grand Theft Auto V leans Execution (Practiced Mastery); Panzer Dragoon II Zwei leans Execution (Practiced Mastery).
Panzer Dragoon II Zwei leans clearly harder on execution.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Panzer Dragoon II Zwei
Multi-directional lock-on aiming on rails tests the hands.
Grand Theft Auto V leans clearly harder on reads.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Panzer Dragoon II Zwei
Enemy waves are fully choreographed.
Grand Theft Auto V leans a little harder on variance, though the gap is small.
Grand Theft Auto V
Some mission and lobby randomness.
Panzer Dragoon II Zwei
Runs are deterministic once memorized.
Panzer Dragoon II Zwei leans a little harder on optimization, though the gap is small.
Grand Theft Auto V
Heists, money loops, builds learnable.
Panzer Dragoon II Zwei
Route branches and dragon evolution reward memorized play.
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.